Broken knife detecting device for printing circuit board hole drilling machine

The utility model relates to a broken knife detecting device for a printed circuit board driller, which relates to a printed circuit board driller, particularly a broken knife detecting device of the printed circuit board driller. The utility model comprises a control system, a signal acquisition circuit and a signal processing circuit, wherein the signal acquisition circuit is connected with a drill knife and a printed circuit board, the signal acquisition circuit is connected with the signal processing circuit through a coupling circuit and the signal processing circuit is connected with the control system. The utility model has the advantages of simple structure of the detecting device, rapid and accurate detection of the positions of a broken knife and high durability, and regardless of the size of the diameter of the drill knife, the detection can be rapid and reliable as the same.